Consistent Query Answering over Inconsistent Databases

This paper addresses the problem of managing inconsistent databases, that is, databases violating integrity constraints. Most of the works dealing with the problem of extracting reliable information from inconsistent databases are based on the notion of repair, a “minimal” set of update operations which leads the database to a consistent state (called repaired database), and the notion of consistent query answer, a query answer that can be obtained from every repaired database. The problem of computing consistent query answers in the presence of different classes of constraints and under different repair strategies is analyzed.